diff --git a/How-to-use-the-4G-extension.md b/How-to-use-the-4G-extension.md
index a8c9df6..9d4e1f2 100644
--- a/How-to-use-the-4G-extension.md
+++ b/How-to-use-the-4G-extension.md
@@ -48,7 +48,7 @@ blacklist cdc_wdm
 EOF'
 ```
 
-`ttyUSB2` is what we want,but **cdc-wdm0** is still worth to try if you know it well 
+`ttyUSB2` is what we want,but **cdc-wdm0** is still worth to try if you knew it well 
  
 ### Create 4g net connection and bring it up